Clamp arrangement



Oct. 22, 1968 J. P. DOERING, JR

CLAMP ARRANGEMENT Filed July 1, 1966 FIG: 5

FIG: 3

JOHN P. DOERING JR FIG 7 ATTORNEY nited States Patent 3,406,996 CLAMP ARRANGEMENT John P. Doering, J12, 2116 Greenbrier St., Santa Ana, Calif. 92706 Filed July 1, 1966, Set. No. 562,367 3 Claims. (Cl. 292256) ABSTRACT OF THE DISCLGSURE A clamping arrangement for holding together two housing sections including upstanding lug members protruding frommating portions of the two housing sections and a spring clip member engaging the rear surfaces of the lugs and forcing the lugs attached to opposite housing sections in opposite directions thereby forcing the mating surfaces of the respective housing sections into abutting relationship, the stress in the spring clip holding the housing sections together and retaining the spring clip in place against the protruding lugs.

The present invention relates to a clamp arrangement ment and is more particularly directed to a clam-ping arrangement for holding together two sections of a housing, such as a potentiometer housing or the like.

The housing for many types of electrical apparatus is formed in two separate sections adapted to be connected together in abutting relationship after the electrical apparatus is assembled and inserted therein. For example, a potentiometer housing sometimes comprises a first cuplike section and a second cup-like section each having similar external proportions and being adapted to abut together around the open ends thereof to enclose a cavity. Sometimes the potentiometer includes a first housing section enclosing a cavity and a lid section having similar external proportions adapted to cover the open end of the housing section. Again, in potentiometers, it is sometimes desirable to attach or connect together two or .more potentiometer cases to provide a ganged assembly or composite case assembly that is rigid in construction and accurately aligned with the individual housings or case units rotatably adjustable one with respect to the other.

A common clamping means employed for this purpose in the past has utilized a clamp ring or band having overlapping edge sections which tighten around the abutting edge portions of the respective housing sections to hold them together in abutting relationship. Such a band when installed around the outer periphery usually increases the total package size and, if recessed into the edge portions of the respective housing sections, the band sometimes weakens such sections. The clamping ring also includes an ear or other extension that sticks out and makes it difficult to attach electrical conductors to the terminals of the potentiometers. Further-more, since the band is metal, the terminals, resistors, wiring must be spaced a proper distance from the band in order to pre ,vent voltage breakdown. The band also goes continuously around the potentiometer and occupies a considerable proportion of the outer surface of the potentiometer housing in which nothing can be mounted.

Other means for attaching a pair of housi g sections is to use radial or axial screws adapted to fit through one section and attach to a flange or other means formed in the mating section. This arrangement, of course, requires the use of drilled holes through the respective sections and makes it difficult to change the rotational position of one section with respect to the other section of the housing, which is sometimes necessary in potentiometer devices in order to correct out of phase relationships be- 3,496,996 Patented Oct. 22, 1968 tween the components supported within the respective housing sections.

The above described arrangements are expensive and tend to increase the total cost of potentiometers and other such electrical apparatus. The clamping arrangement of the present invention overcomes many of the above-mentioned disadvantages and is very simple and easy to apply as well as being quite inexpensive in comparison to other known types of clamping arrangements for attaching two housing sections together.

The advantages of the present invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

Briefly, the clamping arrangement of the present invention includes up-standing lug members formed on the external peripheral surfaces of mating housing sections. The lug members have rear surf-aces, facing away from the mating surfaces of the housing. A spring clip member having spring clamping sections engaged with the rear surfaces of the lug members forces the lug members in opposite directions and holds the mating surfaces of the housing sections into abutting relation, the stress of the spring clamping sections not only forcing the two housing sections together but also retaining the spring clip itself in place.

For a better understanding of the invention, reference may be had to the accompanying drawing in which:

FIGURE 1 is a perspective view of two separate housing sections forced into abutting relation by the clamp arrangement of the present invention;

FIGURE 2 is a side view of a pair of housing sections illustrating the clamping arrangement on the upper and lower sides thereof;

FIGURE 3 is a plan view illustrating another embodiment of the spring clip member;

FIGURE 4 is a plan view illustrating another embodiment of the clamping arrangement;

FIGURE 5 is a front elevation view taken substantially along line 55 of FIGURE 4 and illustrating in more detail the potentiometer clamping arrangement of the FIGURE 4;

FIGURE 6 is a clamping arrangement employing only two lugs in abutting relation in a different version of the spring clamping arrangement; and

FIGURE 7 is still another embodiment of the clamping arrangement employing a -U-shaped clamp stressed against a pair of tapered lugs.

Referring now to FIG. 1, there is shown one preferred embodiment of the invention in which the numeral 10 generally-denotes a clamp arrangement. As shown in FIG. 1, the housing includes two housing sections 11 and 13 typically formed of an insulative material, such as diallyl phthalate and having substantially similar outer shape and dimensions. These sections have mating surfaces or faces 11a and 13a respectively which are adapted to be retained in abutting relation. While the sections appeared to be half shell sections, it will be understood that the separate sections could be a large housing section and a mating lid section adapted to cover the cavity of the larger housing section.

Housing section 11 includes a pair of lug members 12 extending outwardly therefrom in the area adjacent the mating surface 11a and housing section 13 includes one lug member 14 extending outwardly from the external surface thereof in an area closely adjacent the mating surface 13a. As will be seen in FIGURE 1, the lug members 12 and 14 are rigidly attached to and may be integrally molded with the housing sections 11 and 13. It will also be understood that the lug members could be formed of upwardly extending pin sections molded or otherwise attached to the respective housing sections.

The two housing sections 11 and 13 are so positioned and arranged that the lug 14 of section 13 is located substantially equidistance between the two lugs 12 extending outwardly from the housing section 11. In the embodiment of FIGURE 1, a spring clip member 15, which is preferably yoke-shaped, is positioned with outwardly extending end portions or extremities abutting against the rear surfaces of lugs 12 while the central portion of the spring clip member is engaged with or abutting against the rear surface of lug 14. The rear surfaces of the respective lugs are those surfaces facing generally in a direction away from the mating surfaces of the housing sections. These rear surfaces are preferably formed so that they protrude from the external surfaces of the housing sections at an angle not substantially greater than 90 so that the force of the lug member against the spring clip is directed in a plane extending longitudinally along the surface of the housing section or toward the surface of the housing section.

The spring clip member 15, as will be seen in FIGURE 1, is so formed that it is still in stress when inserted or threaded between the respective lug members and the mating surfaces of the housing sections are disposed in abutting relation. That is, the respective sections of the spring clip 15, engaging the rear surfaces of the respective lug members continuously exert a force on the rear surfaces of such members tending to force them in opposite directions. Inasmuch as lug members 12 and 14 are rigidly attached to the respective sections 11 and 13, this force exerted against the rear surfaces of the respective lug memmers tends to force the sections 11 and 13 together and hold them together in abutting relation. The stress on the sections of the spring clip memberlS also creates a frictional force between the rear surfaces of the lug members and the engaging surfaces of the spring clip, which securely holds the spring clip 15 in place. If desired, the spring clip 15 may be provided with serrations, in the regions adapted to engage the rear surfaces of the lug members, for more securely holding the clip 15 in place. While the lug 14 is shown in FIGURE 1 as having a rounded rearwardly facing surface, it will be understood that such lug member may also be formed rectangular or square in shape similarly as lugs 12 on housing section 11.

As shown in FIGURE 2, two clamping sets, arranged at substantially 180 apart, are employed for retaining the two sections 11 and 13 of the housing member in place. Obviously, three or more sets of clamping arrangements could be used, if desired.

Another embodiment of the invention is shown in FIG- URE 3 for retaining the housing sections 33 and 34 together. In this embodiment a yoke-shaped spring clip 31, which is formed in a squared clamp shape, abuts against the rearwardly facing surfaces of lugs 35 extending from the section 33 and against the central lug 36 extending from section 34. In this embodiment, the respective sections of the clamp 31 are provided with serrations in order to produce a greater frictional force between the spring clip 31 and the rear surfaces of the respective lug members.

FIGURES 4 and illustrate another embodiment of the invention in which a potentiometer housing including two sections 42 and 44 is held together by a slightly different version of the clamp arrangement. As may be seen in FIGURE 5, this potentiometer housing encloses a potentiometer coil 47 positioned around the interior surface of the housing cavity and includes a movable wiper 48 which is attached to a rotor member 49 adapted to be rotated by a shaft 50, which may be journalled through a bearing 50 formed in the end wall of the housing section 42.

In the clamp arrangement of this embodiment, the lugs 41, extending from housing section 44, and lug member 4, 43, extending from housing section 42, are molded rectangular blocks protruding outwardly from the mating surfaces of the respective sections. Each of the mating surfaces of the respective sections is provided with a corresponding number of slots as there are lugs protruding from the mating surface of the other housing section.

These slots, such as slot 46 shown in FIGURES, are adapted to receive the rectangular shaped lug members of the opposite mating section. Lug members extend into the respective slots permitting the mating surfaces of the respective sections to engage in abutting relationship. The rearwardly facing surfaces of the portions of the lug members protruding above the external surface of the sections are, as in the previously described embodiments, engaged by a spring clip member. In this embodiment, the spring clip member comprises a relatively straight spring section threaded between the rearward facing surfaces of the respective lugs 41 and 43. The force on lug 43, in the embodiment shown in FIGURE 4, is toward the left and the force exerted on lug members 41 is toward the right. Since lugs 41 are attached to section 44, this section is forced toward the right; since lug 43 is attached to section 42, this section is forced toward the left thereby maintaining the two housing sections in abutting relationship. Of course, two or more clamp sets are disposed around the periphery of the housing to securely hold the two housing sections together.

In this embodiment because the rearwardly facing surfaces of the respective lugs are more in alignment than in the previously described arrangements, the spring clip member may preferably be a straight spring wire when it is in its unstressed form. In order to permit phasing or rotation of the one housing section with respect to the other, it may be desirable to make the slots 46 somewhat wider than the width of the corresponding lug members thereby permitting some rotational positioning of the respective housing sections before the spring wire clamp is assembled.

FIGURE 6 discloses another embodiment of the invention in which only one lug member, extending from each of the sections 54 and 55, is required. In this embodiment, lug members 52 and 53, extending from the respective housing sections, are adapted to be moved into abutting relation and a clamp 51, which is in the form of a ring clamp having spread apart arm sections 51a and 51b, forces the respective lugs 52 and 53 toward one another. The spring stress placed upon the spread apart arm sections 51a and 51b of the ring clamp 51 also retains the clamp in position, as in the embodiments described previously.

A similar arrangement to that of FIG. 6 is shown in FIGURE 7. In this embodiment lug members 62 and 63 are adapted to be moved into abutting relation with each other. The rear surfaces, or the surfaces thereof facing generally in a direction away from the mating surfaces of the respective housing sections, are formed with a taper or so that they tend to converge in the same direction. In this embodiment, the spring clip member comprises a U-shaped clamp having a pair of stressed arms 61a and 61b adapted to engage the tapered surfaces of the lug members 62 and 63. The frictional force exerted by the arms 61a and 61b against the converging or tapered surfaces of the lug members 62 and 63 retains the clamp member 61 in place against the lugs and forces the lugs into abutting engagement. This is an extremely simple arrangement and very easily applied. If arms 61a and 61b of the spring clip member are also provided with serrations, the locking action of the spring clamp against the tapered surfaces of the lugs is very effective.

While in accordance with the patent statutes there has been shown and described what at present are considered to be the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is, therefore, the intent of the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What is claimed is: 1. A clamp arrangement for holding together two sections of a potentiometer or the line comprising:

first and second housing sections having external surfaces of substantially similar shape and dimensions about an axis passing through said sections, each of said sections having mating surfaces intersecting said axis and so constructed and arranged as to be positioned together in abutting relationship so that the edges formed between said external surfaces and said abutting surfaces of said respective sections substantially coincide; at least a pair of spaced apart lug members extending outwardly from said first housing section and a single lug member extending outwardly from said second housing section, each of said lug members being in closely juxtaposed position with respect to said mating surfaces of said housing sections, said lugs having rear surfaces facing generally in a direction away from said mating surfaces of said respective sections, said single lug member disposed substantially equidistant between said pair of lug members on said first section, said rear surfaces of each lug member protruding outwardly from said external surfaces of said respective sections at an angle no greater than 90 from said external surfaces; and a spring clip member having opposite end portions thereof disposed against the rear surfaces of said spaced apart lugs attached to said first section and a central portion of said spring clip member disposed against the rear surface of said single lug thereby forcing said mating surfaces of each housing section toward each other into abutting relationship. 2. The clamp arrangement defined in claim 1 in which there are at least a pair of spaced apart lug members extending outwardly from said first section adjacent said mating surface thereof and a single lug member extending outwardly from said second section adjacent the mating surface thereof and said first and second sections are positioned with said single lug member disposed substantially equidistance between said pair of lug members on said first section and said spring clip member comprises a yoke-shaped length of spring wire with opposite ends thereof disposed against the rear surface of said spaced apart lugs on said first section with the central portion of said spring clip member disposed against the rear surface of said single lug thereby forcing said lugs in opposite directions and forcing said mating surfaces into abutting relation.

3. The clamping arrangement defined in claim 1 in which said first housing section includes a pair of spacedapart lug members in the shape of rectangular block members protruding outwardly from said mating surface thereof as well as extending radially outwardly from the external surface of said first housing section, said mating surface of said first housing section including a slot therein between said spaced apart lug members, and said second housing section includes a similar rectangular block shaped lug member protruding outwardly from said mating surface thereof, said mating surface of said second housing section includes a pair of spaced apart slots on opposite sides of said lug member, said lug members and slots on said respective mating surfaces of said first and second sections being so constructed and arranged that said lug members fit within said slots when said housing sections are in abutting engagement.

References Cited UNITED STATES PATENTS 484,663 10/1892 Martin 29287 3,091,487 5/1963 Gallagher 287l30 MARVIN A. CHAMPION, Primary Examiner.

E. J. MCCARTHY, Assistant Examiner.

U.S. DEPARTMENT OF COMMERCE PATENT OFFICE Washington, D.C. 20231 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,406,996 October 22, 1968 John P. Doering, Jr.

It is r'cruiied that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 6, "line" should read like Signed and sealed this 27th day of January 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR. 

